Infusion device with releasable fluid connector

ABSTRACT

An infusion set system includes a base and a fluid connector removably coupleable thereto. The fluid connector includes a fluid path portion and at least one connector latch displaceably connected to the fluid path portion and displaceable to a latching position in which at least a portion of the connector latch extends into the fluid path portion, which includes a cannula extending from a top interior surface thereof, and a plurality of internal sidewalls corresponding to at least two of a plurality of flat side surfaces of at least one of a base section and a base latch, thereby facilitating connection between the base and the fluid connector in a plurality of discrete rotational connecting positions. When the fluid connector is locked to the base, the at least one connector latch engages a base latching portion of the base and restricts proximal displacement of the fluid connector.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/362,104, filed on May 30, 2014, which is the U.S. national stage ofInternational Application No. PCT/US12/68632, filed on Dec. 7, 2012,which claims priority under 35 USC §119(e) from U.S. ProvisionalApplication Nos. 61/568,074, 61/692,985, and 61/719,755 filed on Dec. 7,2011, Aug. 24, 2012, and Oct. 29, 2012 respectively. The disclosure ofeach of these applications is incorporated herein by reference in itsentirety.

FIELD OF THE INVENTION

The present invention relates generally to infusion devices, and moreparticularly, to subcutaneous infusion devices to be used in conjunctionwith an infusion pump in the infusion of insulin and other medicaments.

BACKGROUND OF THE INVENTION

One mode of insulin infusion treatment includes infusion pump therapyvia a catheter, needle or other type of cannula. Infusion pumps offerthe advantages of continuous infusion of insulin, precision dosing, andprogrammable delivery schedules. Together, these advantages result inmore accurate blood glucose control. In this mode of insulin infusiontreatment, the infusion pump remains attached to the user and requireddoses of insulin are delivered to the user via the pump.

One type of cannula is a catheter, which generally is a tube that can beinserted into the body to permit the administration of fluids. Ininfusion pump therapy, the types and sizes of the catheter may vary, butgenerally, the catheter is a thin, flexible tube. In some uses, however,it may be larger and/or rigid. A rigid, hollow, metal needle may also beused in place of a soft plastic catheter.

One type of conventional infusion set is sold as the Quick-Set® infusionset by Medtronic. In such devices, the infusion pump includes a catheterassembly connected to a pump via a tubing set, and a separate insertiondevice inserts and/or attaches the catheter assembly into/to a user viaan introducer needle provided as part of the infusion set. The infusionset and insertion device can also be combined, as in the Mio® infusionset sold by Medtronic, which is an “all-in-one” design that combines theinfusion set and insertion device into one unit.

Another type of insulin infusion device, known as a “patch pump,” hasrecently become available. Unlike a conventional infusion pump, a patchpump is an integrated device that combines most or all of the fluidcomponents in a single housing that is adhesively attached to aninfusion site, and does not require the use of a separate infusion(tubing) set. A patch pump adheres to the skin, contains insulin (orother medication), and delivers the drug over a period of time, eithertransdermally, or via an integrated subcutaneous mini-catheter. Somepatch pumps communicate with a separate controller device wirelessly(such as one sold under the brand name OmniPod®), while others arecompletely self-contained.

A conventional infusion device can include a fluid connector, which maybe releasably attached to a base that can be secured to a user's skin.An infusion pump supplies fluid to a catheter via the fluidconnector/base engagement.

With such devices, however, there are concerns over the difficulty ofbalancing the force required to disconnect the tubing without pullingthe catheter from the user's skin versus having enough retention forceto secure the infusion components for everyday infusion. Another concernis that there may be a need to design a rotational lock between thefluid connector and the base. Yet another concern is that the separationforce needs to be designed such that if a user accidentally snags theextension tubing on an external structure (e.g., a doorknob), theextension tubing will disconnect from the fluid connector withoutremoving the catheter from the user's skin, thus saving the patient fromthe need to obtain, connect and re-insert a new infusion set.

Additionally, to protect the cannula and/or introducer needle prior toinsertion, conventional devices often include a needle guard that isremoved prior to use. These needle guards, however, are often very smalland may be difficult to grasp, particularly for people with impaireddexterity. Additionally, conventional needle guards are often held inplace by friction alone. To remove such needle guards, patients mustpull and/or twist the needle guard, and the axial force required toremove such needle guards may vary widely, for example, based onmanufacturing tolerances. Further, with such needle guards, once thecoefficient of static friction is overcome, the guard may separatequickly, without providing an opportunity for a user to modify theapplied force and potentially resulting in a needle-stick injury.Further, there is a risk that the needle guard can contact the needleduring removal, potentially dulling the cannula or introducer needle.

SUMMARY OF THE INVENTION

An object of embodiments of the present invention is to substantiallyaddress the above and other concerns, and provide improved infusiondevices. Another object of embodiments of the present invention is toprovide an infusion device configured to balance the separation forceneeded to separate an extension tube from an inserted catheter with theretention force needed to maintain engagement between the extension tubeand inserted catheter, to provide efficient infusion while preventingaccidental removal of the catheter.

These and other objects are substantially achieved by providing aninfusion set system, including a base attachable on a distal sidethereof to a patient at an infusion site, and a fluid connectorremovably coupleable to the base. The base includes a base sectionextending proximally from a surface of the base, a latching portionextending proximally from the base section, and a base latch extendingproximally from the latching portion. The latching portion has a smallerlateral width than the base latch. At least one of the base section andthe base latch has a plurality of substantially flat side surfaces.

The fluid connector includes a fluid path portion and at least oneconnector latch displaceably connected to the fluid path portion anddisplaceable to a latching position in which at least a portion of theconnector latch extends into the fluid path portion. The fluid pathportion includes a cannula extending from a top interior surface of thefluid path portion, and a plurality of internal sidewalls correspondingto at least two of the plurality of the flat side surfaces of the atleast one of the base section and the base latch, thereby facilitatingconnection between the base and the fluid connector in a plurality ofdiscrete rotational connecting positions. When the fluid connector islocked to the base, the at least one connector latch engages thelatching portion of the base and restricts proximal displacement of thefluid connector relative to the base.

These and other objects are also substantially achieved by providing atwo-piece fluid connector that includes a fluid path portion and alatching portion secured to the fluid path portion and having at leastone displaceable arm. The fluid path portion includes a cannula integralwith and extending from a proximal interior surface of the fluid pathportion. The arm includes a connector latch disposed at a first end ofthe arm, and an activation lever disposed at an opposite end of the arm.The connector latch is displaceable to a latching position in which atleast a portion of the connector latch extends into an interior of thefluid path portion through side walls of the fluid path portion.

These and other objects are also substantially achieved by providing aseptum that includes a peripheral portion having a substantiallystraight external side and a peripheral thickness along a first axissubstantially parallel to the external side, and a web portionsurrounded by the peripheral portion, the web portion having a centralportion surrounded by a connecting portion connecting the centralportion with the peripheral portion. The central portion has a maximumcentral thickness along the first axis that is substantially less thanthe peripheral thickness and greater than a minimum thickness of theconnecting portion along the first axis.

These and other objects are also substantially achieved by providing aneedle guard for guarding a sharp cannula of an infusion device. Theneedle guard includes a proximal portion for connecting to the base ofthe infusion device, and a distal portion for user interaction. Theproximal and distal portions each include at least one axial cutout thatdivides the needle guard into first and second lateral sides. A fulcrumweb is disposed between the proximal and distal axial cutouts to jointhe first and second lateral sides of the needle guard and provide afulcrum for relative rotation of the first and second lateral sides ofthe needle guard.

Additional and/or other aspects and advantages of the present inventionwill be set forth in the description that follows, or will be apparentfrom the description, or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The various objects, advantages and novel features of the exemplaryembodiments of the present invention will be more readily appreciatedfrom the following detailed description when read in conjunction withthe accompanying drawings, in which:

FIG. 1 is a perspective view of a needle hub connected to an infusionset base in accordance with an exemplary embodiment of the presentinvention;

FIG. 2 is a cross-sectional view the needle hub and base of FIG. 1;

FIG. 3 is a perspective view of the base of FIG. 1;

FIG. 4 is a cross-sectional view of the base of FIG. 1;

FIG. 5 is a perspective view of a fluid connector attached to the baseof FIG. 1 in accordance with an embodiment of the present invention;

FIG. 6 is a cross-sectional view of the fluid connector and base of FIG.5;

FIG. 7 is an exploded view of the needle hub of FIG. 1;

FIG. 8 is an exploded view of the fluid connector and base of FIG. 5;

FIG. 9 is perspective view of the fluid connector of FIG. 5 and areservoir connector;

FIG. 10 is another cross-sectional view of the fluid connector and thebase of FIG. 5;

FIG. 11 is an exploded view of the fluid connector of FIG. 5;

FIG. 12 illustrates opposing perspective views and a cross-sectionalview of a split septum in accordance with an exemplary embodiment of thepresent invention;

FIG. 13 illustrates a side view of a septum having a convex top surfaceand a cross-sectional view of a base receiving the septum in accordancewith an exemplary embodiment of the present invention;

FIG. 14 is a side view of a septum having a concave top surface and across-sectional view of a base receiving the septum in accordance withan exemplary embodiment of the present invention;

FIG. 15 is a top view of a straight-sided split septum having ahexagonal shape in accordance with an exemplary embodiment of thepresent invention;

FIG. 16 is a top view of a straight-sided split septum having a squareshape in accordance with an exemplary embodiment of the presentinvention;

FIG. 17 is a top view of a straight-sided split septum having apolygonal shape in accordance with an exemplary embodiment of thepresent invention;

FIG. 18 is a top view of a straight-sided split septum having ahexagonal shape in accordance with an exemplary embodiment of thepresent invention, the figures schematically illustrating retentionforces acting on center slit;

FIG. 19 is a top view of a related art straight-sided split septumhaving a circular shape, the figure schematically illustrating retentionforces acting on a center slit;

FIGS. 20 and 21 are perspective and cross-sectional views, respectively,of a septum in accordance with an exemplary embodiment of the presentinvention;

FIGS. 22 and 23 are cross-sectional vies of respective septa inaccordance with exemplary embodiments of the present invention;

FIGS. 24 and 25 are perspective and cross-sectional views, respectively,of a septum in accordance with an exemplary embodiment of the presentinvention;

FIGS. 26 and 27 are perspective and cross-sectional views, respectively,of a septum in accordance with an exemplary embodiment of the presentinvention;

FIGS. 28 and 29 are perspective, cross-sectional vies of respectivesepta in accordance with exemplary embodiments of the present invention;

FIG. 30 is a cross-sectional view of a wedge used with the base of FIG.5 in accordance with an exemplary embodiment of the present invention;

FIG. 31 is a perspective view of a needle shield device in accordancewith an exemplary embodiment of the present invention;

FIGS. 32-36 are perspective cross-sectional views illustrating operationof the needle shield device of FIG. 31;

FIG. 37 is a perspective and cross-sectional view of an infusion devicewith an introducer needle hub in accordance with an exemplary embodimentof the present invention;

FIG. 38 is a perspective view of a fluid connector and base fullyengaged in accordance with an exemplary embodiment of the presentinvention;

FIGS. 39-41 illustrate latching between the fluid connector and baselatches of FIG. 38;

FIGS. 42-44 illustrate components of a fluid connector, fluid connectorlatches, and activation levers in accordance with an exemplaryembodiment of the present invention;

FIGS. 45-55 illustrate release liner slit designs for peeling theadhesive backing off of an adhesive patch connected to an infusiondevice in accordance with another exemplary embodiment of the presentinvention;

FIG. 56 is a perspective view of a base in accordance with an exemplaryembodiment of the present invention;

FIG. 57 is an exploded, perspective view of a fluid connector inaccordance with an exemplary embodiment of the present invention;

FIG. 58 is an assembled perspective view of the fluid connector of FIG.57;

FIG. 59 is an assembled cross-sectional view of the base of FIG. 56 andthe fluid connector of FIG. 57;

FIG. 60 is a perspective cross-sectional view of the fluid connector ofFIG. 57;

FIG. 61 is a bottom view of the fluid connector of FIG. 57;

FIG. 62 is a front cross-sectional view of the fluid connector of FIG.57;

FIG. 63 is an assembled perspective view of the base of FIG. 56 and thefluid connector of FIG. 57;

FIGS. 64 and 65 are exploded and cross-sectional views, respectively, ofthe base of FIG. 56;

FIG. 66 is a perspective view of a fluid connector having a finger griprelease mechanism in accordance with another exemplary embodiment of thepresent invention;

FIG. 67 is a side view of the fluid connector of FIG. 66 connected witha base in accordance with exemplary embodiment of the present invention;

FIG. 68 is a perspective view of the base of FIG. 67;

FIG. 69 is a perspective, bottom view of the fluid connector of FIG. 66;

FIG. 70 is a perspective, cross-sectional view of the fluid connector ofFIG. 66;

FIG. 71 is a perspective, cross-sectional view of the fluid connector ofFIG. 66 connected with the base of FIG. 67;

FIG. 72 is a perspective view of a latching portion of the fluidconnector of FIG. 66;

FIG. 73 is a perspective, cross-sectional view of the base of FIG. 67;

FIG. 74 is a cross-sectional view of a wedge in accordance with anexemplary embodiment of the present invention;

FIGS. 75 and 76 are perspective top and bottom views, respectively, of afluid connector in accordance with another exemplary embodiment of thepresent invention;

FIG. 77 is a perspective view of a base in accordance with anotherexemplary embodiment of the present invention;

FIGS. 78-81 are partial cross-sectional views of bases in accordancewith exemplary embodiments of the present invention;

FIG. 82 is a cross-sectional view of a base in accordance with anotherexemplary embodiment of the present invention;

FIG. 83 is a bottom perspective view of a fluid path portion of a fluidconnector in accordance with another exemplary embodiment of the presentinvention;

FIG. 84 is a partial cross-sectional view of a base in accordance withanother exemplary embodiment of the present invention;

FIG. 85 is a perspective view of an infusion set assembly in accordancewith an embodiment of the present invention;

FIG. 86 is a perspective view of a needle guard in accordance with anembodiment of the present invention;

FIG. 87 is a bottom perspective view of the needle guard of FIG. 86;

FIG. 88 is a top view of the needle guard of FIG. 86;

FIG. 89 is a side view of the needle guard of FIG. 86;

FIG. 90 is a perspective cross-sectional view of the needle guard ofFIG. 86 taken along the line 90-90 of FIG. 89;

FIG. 91 is a perspective cross-sectional view of the needle guard ofFIG. 86 taken along the line 91-91 of FIG. 88;

FIGS. 92 and 93 are cross-sectional views of the needle guard of FIG. 86shown connected to a base of an infusion set;

FIG. 94 is a perspective view of a fluid connector connected with tobase of FIG. 92, which is connected to the needle guard of FIG. 86;

FIGS. 95-97 illustrate an infusion base 600 in accordance with anotherembodiment of the present invention; and

FIG. 98 is a cross-sectional view of a metal wedge 640 in accordancewith an embodiment of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Reference will now be made in detail to an embodiment of the presentinvention, which is illustrated in the accompanying drawings, whereinlike reference numerals refer to like elements throughout. Theembodiment described herein exemplifies, but does not limit, the presentinvention by referring to the drawings. As will be understood by oneskilled in the art, terms such as up, down, bottom, top, proximal, anddistal are relative, and are employed to aid illustration, but are notlimiting.

FIG. 1 illustrates an exemplary embodiment of an infusion set comprisingan introducer needle hub 100 engaged with a base 102. The base 102engages a flexible disc 104 positioned between the base 102 and a user.The flexible disc 104 provides improved comfort and mobility of thedevice because it moves with the user during physical activity whileminimizing contact of the rigid portions of the base 102 with the user.The flexible disc 104 is attached to an adhesive patch or pad 106 havingan adhesive backing, which is used to secure the base 102 to the user'sskin. FIG. 1 illustrates a state in which the introducer needle hub 100and base 102 are ready to facilitate insertion of a soft (flexible)catheter 108 and an introducer needle 110 into the user.

FIG. 2 is a cross-sectional view of the base 102 and introducer needlehub 100 configuration shown in FIG. 1. The introducer needle 110 isfixed to a needle mounting structure 112 within the introducer needlehub 100, thus fixing the introducer needle 110 against axial movementrelative to the hub 100. The introducer needle hub 100 is used to insertthe introducer needle 110 and the catheter 108 into the user withoutrequiring the user to hold or manipulate the introducer needle 110directly. The introducer needle 110 is preferably a hollow stainlesssteel needle with a sharp beveled distal end.

FIGS. 2-4 further illustrate features of the base 102. The base 102includes a columnar post 113 surrounding an internal cavity 116. Amushroom-shaped base latch 114 is disposed at the proximal end of thepost 113. The internal cavity 116 generally extends through the centerof the base 102 providing a fluid passageway through the base 102. Asshown, for example, in FIG. 2, the internal cavity 116 of the base 102receives a retaining wedge 118 and a catheter 108. The wedge 118 has afunnel shape with a hollow center portion that narrows from a broad endto a narrow end 120. The narrow end 120 of the wedge 118 has a taperedend used to receive a terminal end of the catheter 108. The catheter 108is forced over the narrow end 120 of the wedge 118 and thewedge/catheter assembly is inserted into the internal cavity 116 of thebase 102.

Due to the flexible characteristics of the catheter 108, it may have atendency to bunch up within the base 102 and therefore, the base 102provides an additional cavity area 122 to accommodate excess catheter108 material that may accumulate within the base 102 during theinstallation of the catheter onto the wedge 118. A pre-slit resilientseptum 124 is also retained within the internal cavity 116 of the base102. According to an exemplary embodiment, the septum 124 is held inplace within the base 102 by a press fit, which provides a frictionforce between the septum 124 and both the base 102 and the wedge 118.Alternatively, the septum 124 may be fixed within the base 102 by anadhesive or by swaging plastic material from the base 102 over the topof the septum, or a combination of the above-described methods.

FIGS. 3 and 4 also illustrate first and second molded shots used inmanufacturing base 102. The second molded shot (disc 104) may be of thesame material as the first shot or may be of a different, more flexiblematerial, which may include a silicone or thermoplastic elastomer, andthus, may be the flexible disc 104. As shown in FIG. 3, cutouts or holes103 in the base 102 become filled with the material for the flexibledisc 104, and thus, facilitate bonding between the base 102 and theflexible disc 104.

FIGS. 5 and 6 illustrate a fluid connector or fluid connector 126connected to the base 102, and FIG. 7 illustrates an exploded view ofthe introducer needle hub 100 and base 102. The fluid connector 126includes activation levers 128, fluid connector latches 130, and a rigidstop 132 (best shown in FIG. 11). The user attaches the fluid connector126 to the base 102 by pressing the fluid connector axially down ontothe base 102 and snapping it in place. In this process, the latches 130and activation levers 128 resiliently deflect to allow the latches topass over the mushroom-shaped base latch 114. Subsequently, the latches130 and activation levers 128 return substantially to their undeformedor less deformed positions with the latches resiliently engaging theunderside of the mushroom-shaped base latch 114 to prevent axialdisplacement of the fluid connector 126 relative to the base 102. Inother words, during connection, the fluid connector latches 130 slideover the mushroom-shaped base latch 114 and resiliently return to aposition where they snap and engage the base 102 via engagement with thepost 113 and the base latch 114.

The user removes the fluid connector 126 by pressing the activationlevers 128 together until they engage the rigid stop 132, therebydisengaging the latches 130 from the mushroom-shaped base latch 114.Then the user then lifts the fluid connector 126 axially away from thebase 102

In this exemplary embodiment, the activation levers 128 and the fluidconnector latches 130 are molded from a resilient plastic material as aseparate component from the fluid connector 126. The activation levers128 and fluid connector latches 130 pivot on a living hinge. This maysimplify manufacturing and reduce mold complexity. The rigid stop 132ensures that both of the fluid connector latches 130 travel far enoughto completely disengage from the mushroom-shaped base latch 114. Therigid stop 132 also provides a stable anchor for the activation levers128 during the handling of the fluid connector 126. Further, the rigidstop 132 prevents the fluid connector 126 from rocking when connected tothe base 102. Additionally, according to one embodiment, the fluidconnector 126 can freely rotate 360 degrees about the base 102, whichprovides the user with the ability to position the extension tubing 134,which connects the fluid connector 126 to an infusion pump.

FIGS. 8 and 9 illustrate an exploded and perspective view, respectively,of the components of an exemplary embodiment of an infusion set. Theinfusion set includes the fluid connector 126 and the base 102 asdescribed above, and also includes the extension tubing 134 connectingthe fluid connector 126 to a reservoir connector 136 that connects to aninfusion pump, as well as a base adhesive 105 for connecting theadhesive patch 106 to the base 102 and/or the flexible disc 104, and anadhesive backing 107 for selectively protecting the distal adhesivesurface of the adhesive patch 106.

FIG. 10 is a sectional view depicting a connected fluid path provided bythe fluid connector 126 and the base 102. In this embodiment, theextension tubing 134 is connected to a tubing port 138 on the fluidconnector 126. According to one embodiment, the tubing port 138 providesa press fit connection for the extension tubing 134, facilitating fluidflow from the infusion pump, through the extension tubing 134 and intothe fluid connector 126. According to another embodiment, glue, oranother bonding mechanism, such as solvent bonding, is used to securethe extension tubing 134 to the tubing port 138. The fluid pathcontinues from the tubing port 138 into a molded cannula 140.

The molded cannula 140 extends in a direction substantiallyperpendicular to the longitudinal direction of the tubing port 138. Inthis embodiment, the molded cannula 140 is a rigid, substantiallytubular member made of plastic and having either a tapered or roundedterminal end. The terminal end of the molded cannula 140 is used topenetrate through a pre-formed slit in the septum 124, thus providing asealed fluid connection between the extension tubing 134 and thecatheter 108. Fluid flows through the molded cannula 140, through theseptum 124, then through the wedge 118 and into the catheter 108. Theseptum 124 provides a self-sealing feature, preventing fluid fromexiting or leaking out of the base 102, except through the catheter 108.According to one embodiment, the molded cannula 140 is formed as anintegral part of the fluid connector 126.

FIG. 11 is an exploded, perspective, cross-sectional view of the fluidconnector 126. In this exemplary embodiment, the fluid connector 126 isformed using two distinct components: a first component 153, includingthe fluid connector latches 130 and the corresponding activation levers128, and a second component 155, including the fluid connector shroud142 (the top half of each component being omitted for clarity). Theactivation levers 128 have finger bumps 144 to aid the user in locatingand using the activation levers 128. Alternatively, the finger bumps 144may be replaced with a ridge or divots that can provide tactile feedbackto the user regarding where to press to release the fluid connector 126from the base 102. According to one embodiment, the activation levers128 can have a different color than the fluid connector 126 to provide avisual indicator for the same purpose. The fluid connector shroud 142 ofthe fluid connector 126 has a smooth rounded exterior surface that aidsin minimizing snagging or catching the fluid connector 126 on clothingor other objects during use. At the base of the fluid connector 126there is a circular anchoring ring 146. The anchoring ring 146 forms afoundation and provides added stability around the base 102 when thefluid connector 126 engages with the base 102.

FIG. 11 also illustrates how the fluid connector shroud 142 and thefluid connector latches 130 are assembled. A male T-slot 148 feature onthe first component 153 engages with a female T-slot 150 feature on thesecond component 155. Detents 152 and 154 on the first and secondcomponents 153 and 155 provide a mechanical lock between the twocomponents. Alternatively, the fluid connector latches 130 and the fluidconnector shroud 142 can be formed as a single integral molded plasticpiece.

FIG. 12 illustrates the self-sealing resilient septum 124, which has apre-pierced center 156 (shown partially opened for illustrativepurposes) to receive the blunt molded cannula 140 from the fluidconnector 126 and facilitate penetration of the septum 124. According toone embodiment, the septum 124 is under inward radial compression toensure a seal at all times, with or without the molded cannula 140 beingpresent. The septum 124 can be made of a soft resilient materialincluding, but not limited to silicones, isoprene rubbers, or bromobutylrubbers. The septum 124 can be made from a combination of thesematerials as well. The septum 124 ensures a complete seal duringinfusion and when the fluid connector 126 is disconnected from the base102. The slit geometry of the septum 124 may be a single straight slitor multiple, intersecting straight slits. The slit may also be curved toensure a complete seal during infusion and while the connecter hub 126is disconnected from the base 102.

FIG. 13 illustrates another exemplary embodiment of a septum 158 for usein the base 102. In this embodiment, the septum 158 has a convex topsurface that can be more easily swabbed and can also aid in keeping thetop center portion of the septum 158 free from glue or debris that mayremain on the septum after it is secured to the base 102. All the septadescribed herein can be secured to the base by a friction fit, swaging,an adhesive, or a combination thereof. The convex top surface of theseptum 158 also provides additional sealing pressure, keeping thepre-pierced slit sealed, particularly when external forces are appliedto the septum 158 when a fluid connector is disconnected from the base102.

FIG. 14 illustrates an alternative exemplary embodiment of the septum160 for use in the base 102. In this embodiment, the septum 160 has aconcave top surface that can aid in centering the molded cannula 140when the fluid connector 126 is engaged with the base 102.

FIG. 15 is a top view of a straight-sided split septum 162 having ahexagonal shape. Assuming the base 102 has a corresponding hexagonalshape, the straight sides allow compression of the septum 162 to have atleast a component of the force that acts in a direction that isperpendicular to the slit in the septum 162. And for the sides that areparallel to the slit, all of the compression forces from those sides aredirected perpendicular to the slit. Further, if the septum 162 is onlycompressed on sides parallel to the slit, then all the compression forceis directed perpendicular to the slit. This ensures that the septum 162is always sealed.

Similarly, FIG. 16 is a top view of a straight-sided split septum 164having a square shape, and FIG. 17 is a top view of a straight-sidedsplit septum 166 having a polygonal shape.

FIG. 18 schematically illustrates the direction of the retention forcesacting on the center slit 168 of the septum 162. In contrast, FIG. 19 isa top view of a conventional straight-sided split septum 170 having acircular-shaped cross-section. FIG. 23 also schematically illustratesthe retention forces acting on the center slit 172, creating forces thatact to both open and close the slit 172.

Respectively, FIGS. 20 and 21 are perspective and cross-sectional viewsof a septum 161 in accordance with another exemplary embodiment of thepresent invention. The septum is substantially a rotational solid with athick inner wall 163 (about 0.07″ (1.7 mm)), an outer band 165 with anexterior face 167 that has a reduced thickness (about 0.03″ (0.76 mm)),compared with the thick inner wall 163, to reduce surface area contact,and thus friction, with the base 102. According to one embodiment, theseptum 161 has a diameter of about 0.126″ (3.2 mm).

The radially inward face 169 of the inner wall 163 is sloped, and has anincluded angle of about 45 degrees. Connecting the face 169 is a centralhorizontal portion or web 171 that is slightly thicker at its centralportion than where it meets the face 169, and vertically, is centrallylocated. The angle α represents the taper of the web 171, and is aboutfourteen degrees. According to one embodiment, the septum 161 has acentral slit. The web 171 includes convex top and bottom surfaces thatcontain the slit. These convex surfaces provide additional sealingpressure, keeping the slit sealed, particularly when external forces areapplied to the septum 161 when the fluid connector 126 is disconnectedfrom the base 102.

The septum 161 includes symmetric concave surfaces (formed by the slopedinward face 169) on both the top and bottom surfaces that aide incentering a cannula (such as cannula 140) through the slit in the septum161 during assembly and improve the sealing ability of the septum 161with respect to the cannula.

FIGS. 22 and 23 are cross-sectional views of septa 220 and 222 that aresimilar to septum 161 in most respects. In septum 220, the face 224connecting the inner wall 226 with the exterior face 228 is beveled atabout 45 degrees, in contrast to the concave shape of the septum 161.Septum 222 is substantially similar to septum 220, except that theinward face 230 is substantially vertical, rather than being sloped.

Respectively, FIGS. 24 and 25 are perspective and cross-sectional viewsof a septum 232 in accordance with another exemplary embodiment of thepresent invention. In comparison to the septa of FIGS. 20-23, the septum232 has a thicker central web 234 (about 0.03″ (0.76 mm)). The angle αof the slope of the web 234 is about thirteen degrees. The bottom ofseptum 232, however, is substantially similar to the bottom of septum161. It will be understood by one skilled in the art that the terms“bottom” and “top” are used in reference to the drawings, and are notlimiting. The bevel angle β at the top of the septum 232 is about 41degrees. The included angle γ is about 46 degrees. Also, in comparisonto the septa of FIGS. 20-23, the exterior face 236 is thicker, therebyincreasing the surface area contact with the base 102.

Respectively, FIGS. 26 and 27 are perspective and cross-sectional viewsof a septum 238 in accordance with another exemplary embodiment of thepresent invention. The top of septum 238 is substantially similar to thetop of septum 232 of FIGS. 24 and 25. The bottom of septum 238, however,is substantially a mirror image of its top. In other words, the septum238 is substantially symmetrical, both vertically and horizontally.

As shown in FIG. 28, the septum 240 has a peripheral portion 241 with asubstantially straight external side or outer face 244. The peripheralportion 241 is the thickest portion of the septum 240. The peripheralportion 241 surrounds a web portion or central web 242. The web portion242 has a central portion 243 surrounded by a connecting portion 245that connects the central portion 243 with the peripheral portion 241.The central portion 243 has a maximum central thickness that issubstantially less than the thickness of the peripheral portion.Additionally, the maximum thickness of the central portion 243 isgreater than a minimum thickness of the connecting portion 245.

Similar to the septa of FIGS. 24-27, the septum 240 of FIG. 28 has athicker central web 242 than the septa of FIGS. 20-23. In contrast tothose septa, however, the web portion 242 is not located at a verticalcenter of the septum 240. Instead, the web portion 242 is much closer tothe top of the septum 242. According to one embodiment, this promotessealing with a penetrating blunt cannula. In addition to the positioningof the web 242, in comparison to the septa of FIGS. 24-27, the outerface 244 is substantially straight and vertical. According to oneembodiment, however, the outer face 244 can have a slight taper at itsends.

The septum 240 also has at least one nub 246 on its top and at least onenub 246 on its bottom. The plurality of nubs 246 disposed on the top andbottom of the septum 240 can aid manufacturing by helping to keep thesepta 240 separate in a container or bin. Additionally, the number ofnubs 246 on top of the septum 240 can be different than the number ofnubs 246 on the bottom of the septum 240, thus permitting visualinspection (including automated visual inspection) during the assemblyprocess to determine if an asymmetric septum is correctly oriented inthe base.

Further, according to one embodiment, during installation of the septum240 in a base, the septum 240 designed to be radially compressed byabout 0.012 inches to 0.018 inches (about 0.305 mm to 0.457 mm). Thisinterference between the septum 240 and the base improves septum sealintegrity, both when the fluid connector is attached and when it isdetached. Additionally, according to one embodiment, this interferencebetween the septum 240 and the base slightly puckers the web portion 242to improve re-sealing of the septum 240 when the cannula is removed.Moreover, it is believed that the design of septum 240 provides reliablefluid path connections without the use of a lubricant on the cannula. Inaddition, according to one embodiment, the design of the septum 240allows for a height of only about 0.05 inches (1.35 mm), therebyproviding the ability to reduce the overall height of the infusion set.

The top of the septum 248 of FIG. 29 is substantially similar to the topof septum 240 of FIG. 28, and the bottom of the septum 248 issubstantially similar to the bottom of septum 161 of FIGS. 20 and 21.This results is a slightly thicker central web 250.

The septa of FIGS. 12-29 can be pre-slit. Alternatively, the septa ofFIGS. 12-29 can be formed without having a slit. Additionally, the septaof FIGS. 12-29 can be made of silicones, SBR rubber, bromobutyl rubber,and various polyisoprene formulations.

FIG. 30 illustrates the metal wedge 118 alone. As described above ingreater detail, the catheter 108 fits over the small diameter of thewedge 118 and both components are then inserted into the receivingcavity 116 in the base 102. According to one embodiment, the catheter108 is held in place through a press-fit between these three components.Some catheter material may bunch up during assembly into the base 102.Therefore, a receiving space 122 in the base 102 accommodates this extramaterial so as not to interfere with the desired axial positioning ofthe wedge 118 when assembled. According to one embodiment, the septumcontacts the wedge 118 when installed. According to another embodiment,the septum does not contract 118 when installed.

FIG. 31 illustrates a passive needle shield device 174 connected to thebase 102 and ready for placement on the skin. FIG. 32 is across-sectional view of the needle shield device 174 fully engaged withthe base 102, piercing the septum 124 and the catheter 108 with theintroducer needle 110. The needle shield device 174 includes a needlehub or outer shield 175 which surrounds and encloses an inner shield 176and the introducer needle 110.

FIGS. 33-36 illustrate the sequence of steps that occur after the userhas inserted the catheter 108. In other words, these figures illustratethe operation of removing the needle shield device 174 from the base102. Briefly, the user simply pulls on the outer shield 175 in adirection away from the base 102 to remove the introducer needle 110.According to one embodiment, the outer shield 175 and inner shield 176are both made of rigid plastic materials that have some degree offlexibility.

In more detail, FIG. 33 is a quarter-sectional view illustrating aninitial state of the needle shield device 174 and a first position ofthe outer shield 175 relative to the inner shield 176, in which an outershield hub latch 178 contacts the base 102 and also contacts acantilevered latch beam 180 of the inner shield 174 to maintainengagement of the latch beam 180 with the base 102 beneath the baselatch 114. According to one embodiment, the hub latch 178 biases thelatch beam 180 radially inward.

FIG. 34 illustrates the orientation of the needle shield device 174while the user is axially displacing the outer shield 175, but before ithas completed its stroke relative to the inner shield 176. In thisstate, the outer shield 175 continues to prevent the latch beam 180 fromdisengaging from the base 102. More specifically it is the hub latch 178that holds the latch beam 180 in place against the base 102. Therefore,according to one embodiment, the inner shield 176 is locked onto thebase 102 while the outer shield 175 is being axially displaced relativeto the inner shield 176.

FIG. 35 illustrates the completely displaced position of the outershield 175 with respect to the inner shield 176. In this state, the hublatch 178 no longer prevents the latch beam 180 from disengaging fromthe base 102. The hub latch 178 is instead disposed in an indent 181(best shown in FIG. 32) on the inner shield 176 and engaged with ashield latch 182 formed on the inner shield 176. The shield latch 182engages a top side of the hub latch 178, thereby preventing furtherproximal displacement of the outer shield 175 relative to the innershield 176. Additionally, because the hub latch 178 is no longerpressing on the latch beam 180, the latch beam 180 can disengage fromthe base 102.

Further, a hub beam or outer shield latch 183 rides over an inner shieldlatch 184 and the bottom of the hub beam 183 engages the top of theinner shield latch 184 to prevent distal displacement of the outershield 175 relative to the inner shield 176. According to oneembodiment, the hub beam 183 is cantilevered.

The latch beam 180 is free to radially displace and disengage from thebase 102 once the user continues to distally displace the needle shielddevice 174. The engagement of the shield latch 182 with the hub latch178 and the engagement of the hub beam 183 with the inner shield latch184 shields the introducer needle 110 and thereby reduces thepossibility of an accidental needle stick.

According to one embodiment, the inner shield latch 184 is fixedlydisposed on the inner shield 176. According to another embodiment, theinner shield latch 184 is disposed on a cantilevered inner shield latchbeam 416 so that both the inner shield latch beam 416 and the hub beam183 are cantilevered. According to yet another embodiment, the innershield latch 184 is disposed on a cantilevered inner shield latch beam416 and the hub beam is fixedly disposed on the outer shield 175.

In another alternative embodiment, the needle shield device 174 can alsobe attached to a fluid connector 126 and the base 102. Such anembodiment allows a user to prime the infusion set while it is outsidethe body and insert and remove the introducer needle 110 with the fluidconnector 126 attached the entire time.

FIG. 36 illustrates a completely deployed needle shield device 174. Thelatch beam 180 is removed from the base 102 as the user continues topull on the outer shield 175.

In accordance with another embodiment of the present invention, FIG. 37illustrates an infusion device with an introducer needle hub 186 that isready for insertion into the skin of a user. FIG. 37 is across-sectional view of the introducer needle hub 186, a fluid connector188, and a base 190. Although the introducer needle hub 186 secures andintroduces an introducer needle 192 in substantially the same way as theintroducer needle hub 100 of FIG. 1, the introducer needle hub 186 isconfigured to engage the fluid connector or fluid connector hub 188 andintroduce the introducer needle 192 through the fluid connector 188before penetrating the base 190. The introducer needle hub 186 includesa fluid connector slot 194 that receives a portion of the fluidconnector 188 extending away from the base 190. The fluid connector 188also differs from the previously disclosed fluid connector 126 of FIG. 7in that the top surface of the fluid connector 188 includes an aperture196 for receiving the introducer needle 192. Additionally, to maintain asealed fluid path, a second septum (a first septum being located in thebase) is secured in a cavity 198 immediately adjacent to the aperture.The arrangement shown in FIG. 37 allows the infusion set to be insertedinto the user's skin with the fluid connector already connected to thebase.

FIG. 38 illustrates the fluid connector 188 and base 190 fully engaged.The fluid connector 188 includes activation levers 202, fluid connectorlatches 204, and a rigid stop 206, each made of plastic and functioningsimilarly to the corresponding parts of the previously describedembodiment. In contrast to the previously described fluid connector 126of FIG. 7, however, in this particular embodiment, the activation levers202 and the fluid connector latches 204 are molded as part of the fluidconnector 188 and pivot about a living hinge. This single-piece fluidconnector configuration can be utilized to simplify manufacturing. Therigid stop 206, as disclosed in the previously described embodiment,ensures that both of the fluid connector latches 204 travel far enoughto completely disengage, and provides a stable anchor for the activationlevers 202 during the handling of the fluid connector 188.

FIGS. 39-41 illustrate how the fluid connector latches 204 mate with thebase latches 208. In this exemplary embodiment, the fluid connector 188is latched against rotation with respect to the base 190. The rotationprevention is facilitated by the fluid connector latches 204 droppinginto corresponding base latch slots 210 provided on the column of thebase 190. For clarity, only a portion of the base 190 is shown in FIGS.39-41. During connection of the fluid connector 188 to the base 190, butbefore full engagement, the user can rotate an extension tubing 212 andthe fluid connector 188 so that fluid connector 188 can be convenientlyattached to the infusion pump. If the fluid connector latches 204 do notimmediately drop into the base latch slots 210, slight rotation of thefluid connector 188 can enable the fluid connector latches 204 to dropinto position, thereby locking the fluid connector 188 against removaland further rotation.

If it becomes necessary or desirable to rotate the fluid connector 188and the extension tubing 212, the user simply presses the activationlevers 202 together (as shown in FIG. 41) to disengage the fluidconnector latches 204 from the base latch slots 210. Then, the userrepositions the fluid connector 188 to a more desirable rotational orcircumferential position, and releases the activation levers 202 to lockthe fluid connector latches 204 into the corresponding base latch slots210. FIG. 41 also illustrates a living hinge 209 upon which the fluidconnector latches 204 and activation levers 202 rotate.

In contrast to the embodiment illustrated in FIGS. 39-41, FIGS. 42-44illustrate another embodiment of a fluid connector 213 that includes twomolded plastic components that comprise the fluid connector cover 214,fluid connector latches 216 and activation levers 218. Although thisembodiment includes two separately molded components, the fluidconnector cover 214, fluid connector latches 216, and activation levers218 function in much the same way as the respective componentsillustrated in the embodiment illustrated in FIGS. 39-41. The two moldedplastic components may be utilized, in contrast to a single moldedcomponent, for cosmetics or to simplify manufacturing.

FIGS. 45-55 disclose multiple embodiments of release liner slit designsfor peeling the adhesive backing off of an adhesive patch connected toan infusion device. Each of the embodiments avoids potential contact ofthe release liner with the needle and/or catheter penetrating the centerof the release liner.

FIG. 45 illustrates a first release liner embodiment 282 formed from asingle piece and having two pull tabs 284. In contrast, FIG. 46illustrates a second release liner embodiment 286 formed from a singlepiece and having single pull tab 288 and an extended slit. Similarly,FIG. 47 illustrates a third release liner embodiment 290 formed from asingle piece and having a single pull tab 292 and an off-center slit.FIG. 48 illustrates a fourth release liner embodiment 294 formed from asingle piece and having a single pull tab 296 with an extended slit.FIG. 49 illustrates a fifth release liner embodiment 298 formed from asingle piece and having two pull tabs 300 extending substantially 90degrees from the center slit. FIG. 50 illustrates a sixth release linerembodiment 302 formed from a single piece and having two pull tabs 304extending substantially parallel with the center slit. FIG. 51illustrates a seventh release liner embodiment 306 formed from a singlepiece and having a single pull tab 308 and multiple slits. FIG. 52illustrates an eighth release liner embodiment 309 formed from a singlepiece and having multiple slits and two pull tabs 310 extending fromopposite sides of the release liner and multiple slits. FIG. 53illustrates a ninth release liner embodiment 312 formed from a singlepiece, and having no extending tabs and only a single slit. FIG. 54illustrates a tenth release liner embodiment 314 formed from two piecesand having two pull tabs 316. FIG. 55 illustrates an eleventh releaseliner embodiment 318 formed from two pieces and having two pull tabs 320extending substantially parallel to the slit separating the two pieces.

According to one embodiment, the flexible disc base (for example, base102) can be perforated to increase moisture and air permeability andincrease patient comfort. In another embodiment skin adhesive materialcan be coated directly onto the base, eliminating the need for aseparate adhesive patch. In yet another embodiment, the adhesive patchcan be made from either non-woven or woven adhesive-backed material.

FIG. 56 illustrates features of an exemplary embodiment of a base 326.The base 326 includes a base latch 328 surrounding an internal cavity330. As illustrated, the base latch 328 is formed in an octagonal shape,having eight flat perimeter side surfaces or facets. The base 326 alsoincludes a base section 332 that also includes a plurality of flat sidesurfaces or facets that correspond to the facets of the base latch 328.The flat side surfaces of the base section 332 are also substantiallycoplanar with the corresponding flat side surfaces of the base latch328. Alternatively, the base latch 328 and base section 332 can each beformed having any number of side surfaces, each corresponding to adiscrete rotational or circumferential position. For example, the baselatch 328 and the base section 332 can have three facets. According toanother embodiment, the base latch 328 can have eight or more facets.According to another embodiment, the base latch 328 and the base section332 can have eight or more facets.

Disposed between the base latch 328 and the base section 332 is alatching portion 333 having a reduced diameter compared to the baselatch 328 and the base section 332. According to one embodiment, thelatching portion 333 is a substantially cylindrical column.

According to one embodiment, the base 326 engages a flexible disc 334positioned between the base 326 and the user. The flexible disc 334moves with the user during physical activity while minimizing contact ofthe rigid portions of the base 326 with the user. The flexible disc 334can be attached to an adhesive patch 336 having an adhesive backing,which can be used to secure the base 326 to the user's skin.

FIGS. 57-63 illustrate another exemplary embodiment of a fluid connector338. In comparison to previously-described fluid connectors, thisexemplary embodiment reduces the overall height and profile of the fluidconnector 338, thus reducing interference and potential irritation tothe user. The fluid connector 338 includes two components: a fluid pathportion 339, and a latching portion 343. The latching portion 343includes activation levers 340, fluid connector latches 342, and a rigidstop 344.

According to one embodiment, the activation levers 340, fluid connectorlatches 342, and the rigid stop 344 are integrally formed as a unitarystructure. Additionally, the activation levers 340 form arms with theirrespective fluid connector latches 342. These arms are displaceablerelative to the fluid path portion. The fluid connector latches 342 aredisplaceable to a latching position in which the at least a portion ofhe fluid connector latch 342 is disposed within the fluid path portion339. Further, the arms are resiliently biased toward the latchingposition.

The fluid path portion 339 includes a tubing connector portion 348 forconnecting the fluid connector 338 with tubing. The fluid path portion339 can be secured to the latching portion 343 via snap-fit engagementand in according to one embodiment, the fluid path portion 339 and thelatching portion can be made of the same material.

The user attaches the fluid connector 338 to the base 326 by pressingdistally (down), incrementally forcing the fluid connector latches 342outward, and snapping it in place, due to the inward resilient bias ofthe fluid connector latches 342. The user can also attach the fluidconnector 338 to the base 326 by pressing the activation levers 340together until they engage the rigid stop 344, and then pressing thedistally until internal facets in the fluid path portion 339 engage thebase latch 328 and the base portion 332, as subsequently described ingreater detail. Then, the user releases the fluid connector latches 342so they snap and engage the latching portion 333 and the underside ofthe base latch 328 to resist proximal displacement of the fluidconnector. Once engaged, the user may remove his or her fingers from theactivation levers 340, and the fluid connector 338 will be securelylatched to the base 326. It will be understood by one skilled in the artthat in case the fluid connector 338 gets caught on something, toprevent injury or discomfort to the user, the fluid connector 338 can bedesigned to pull off of the base at a specified force level withoutusing the activation levers 340 due to the flexibility of the fluidconnector latches 342.

To release the fluid connector 338 from the base 326, the user squeezesthe activation levers 340 until they contact the rigid stop 344, therebydisengaging the fluid connector latches 342 from the latching portion333 by pivoting and displacing the fluid connector latches 342 radiallyoutward sufficiently to clear the base latch 328. Then, the user liftsthe fluid connector 328 proximally off of the base 326.

According to one embodiment, the activation levers 340 have finger bumps341 to aid the user in locating and using the activation levers 340.Alternatively, the finger bumps 341 can be replaced with a ridge ordivots that can provide tactile feedback to the user regarding where topress to release the fluid connector 338 from the base 326. According toanother embodiment, the activation levers 340 can have a different colorthan the fluid connector 338 to provide a visual indicator for the samepurpose.

The fluid connector latches 342 include angled planar surfaces 345 thatcorrespond to and engage with the latching portion 333, locking thefluid connector 338 against proximal displacement and each pair ofangled planar surfaces 345 contact the latching portion 333 at twodistinct locations. The angled planar side surfaces 345 are alsosubstantially parallel to the longitudinal axis of the latching portion333. The fluid connector latches also include distal beveled surfaces335 (best shown in FIG. 62) that engage a top surface of the base latch328 during initial connection. As subsequently described in greaterdetail, the engagement of the internal facets of the fluid connector 326with the base latch 328 and the base section 332 prevents rotationalmovement when the fluid connector 326 is engaged with the base 326. Inthis exemplary embodiment, the activation levers 340 and the fluidconnector latches 342 (together as one) are molded as a separate plasticcomponent from the fluid path portion 339. The activation levers 340 andfluid connector latches 342 pivot on a living hinge. The rigid stop 344ensures that both of the fluid connector latches 342 travel far enoughto completely disengage from the base 326, and also provides a stableanchor for the activation levers 340 during the handling of the fluidconnector 338. Additionally, the rigid stop 344 helps prevent rocking ofthe fluid connector when it is attached to the base 326.

As shown in FIG. 59, the internal cavity 330 of the base 326 receives ametal wedge 350 and a catheter 352. The wedge 350 has a funnel shapewith a hollow center portion that narrows from a broad end to a narrowend. The narrow end of the wedge 350 has a tapered edge used to receivea terminal end of the catheter 352. The catheter 352 is forced up thenarrow end of the wedge 350 to form a sealed fluid connection. Apre-slit septum 161 is also retained within the internal cavity 330 ofthe base 326, to receive a cannula 353 of the fluid connector 338.According to an exemplary embodiment, the septum 161 is held in placewithin the base 326 by a press fit, which provides a friction forcebetween the septum 161 and the base 326. The septum 161 (as shown ingreater detail in FIGS. 20 and 21) includes symmetric concave surfaceson both the top and bottom surfaces that aide in centering the cannula353 through the slit in the septum 161 during assembly and improve thesealing ability of the septum 161.

FIGS. 60-62 illustrate various views of the fluid connector 338. FIG. 60is a perspective, cross-sectional view, FIG. 61 is a bottom plan view,and FIG. 62 is a front, cross-sectional view. As shown in FIGS. 60-62,the fluid path portion 339 has a back wall 355 and a plurality ofinternal walls or faces or facets 354. The side walls of the fluid pathportion 339 include respective slots 357 (best shown in FIG. 57) throughwhich the fluid connector hub latches 342 move. As best shown in FIG.62, the top of the interior of the fluid path portion 339 issubstantially dome-shaped and the internal facets 354 and the back wall355 extend all the way to the bottom face 356, even the side walls,which are interrupted by the slots 357.

Referring to FIGS. 56 and 59-62, as the user moves the fluid connector338 distally toward the base 326, the downward sloped, mushroom shape ofthe top of the base latch 328 helps center the fluid connector 338 sothat the cannula 353 aligns with the slit in the septum 161. As thebottom face 356 passes the facets on the base latch 328, the internalfacets 354 and back wall 355 engage the facets of the of the base latch328, thereby fixing the rotational or circumferential orientation of thefluid connector 338 relative to the base 326. According to oneembodiment, the internal facets 354 and back wall 355 engage the facetsof the base latch 338 prior to the cannula 353 penetrating the septum161.

As the user continues to distally displace the fluid connector 338, theinternal facets 354 and the back wall 355 engage the facets of the basesection 332 to enhance the stability of the connection with the base326. According to one embodiment, the bottom face 356 of the fluid pathportion 339 and the bottom face of the rigid stop 344 contact the base326 to further enhance the stability of the connection of the fluidconnector 338 with the base 326.

FIGS. 64 and 65 respectively illustrate an exploded view and anassembled cross-sectional view of the base 326, the wedge 350, theseptum 351, and the cannula 352 described above.

FIG. 66 illustrates another exemplary embodiment configured to reducethe overall height and profile of the fluid connector 360. Fluid hub 360differs from previous embodiments by including a substantially planartop surface, as opposed to having a dome-like shape. The shape of thefluid connector 360 substantially reduces the overall height of thedevice. Similar to the embodiment disclosed in FIGS. 57-65, the fluidconnector 360 includes activation levers 362 and a rigid stop 364. Dueto the lower profile of the fluid connector 360, the rigid stop 364 alsoserves as a tube port 364 for engaging tubing 366. The activation levers362 have finger bumps 368 to aid the user in locating and using theactivation levers 362. Alternatively, the finger bumps 368 can bereplaced with other exemplary embodiments discussed previously. Thefluid connector 360 also includes a groove 370 that receives a bentcannula 372 (more clearly visible in FIG. 92). The bent cannula 372 hasa bent shape that corresponds to the outer perimeter of the fluidconnector 360 and is received inside the tube port 364, providing afluid path between the tubing 366 and a base 374.

The base 374 is substantially similar to that disclosed in FIGS. 56-65.As shown in FIGS. 67, 68, and 71, the base 374 includes a base latch 376surrounding an internal cavity 378. As illustrated, the base latch 376is formed in an octagonal shape, having eight perimeter side surfaces orfacets. The base 374 also includes a base section 380 that includes aplurality of side surfaces that correspond to the side walls of the baselatch 380, each facet corresponding to a different rotational orcircumferential position with respect to the fluid connector 360.Alternatively, the base latch 376 and base section 380 can each beformed having a different number of side surfaces. According to oneembodiment, the base 374 engages a flexible disc 382 positioned betweenthe base 374 and the user. The flexible disc 382 can be attached to anadhesive patch 384 having an adhesive backing, which can be used tosecure the base 374 to the user's skin.

FIGS. 67-72 illustrate additional views of the fluid connector 360 andthe base 374. The fluid connector 360 includes fluid connector latches386 which extend from the activation levers 362. The user attaches thefluid connector 360 to the base 374 by snapping it in place or bypressing the activation levers 362 together until they engage the rigidstop 364, moving the fluid connector 360 distally, and then moving fluidconnector latches 376 to a position where they snap and engage the base374 via engagement with the latching portion 381 (see FIG. 68). Onceengaged, the user may remove his or her fingers from the activationlevers 362, and the fluid connector 360 will be securely latched to thebase 374.

The fluid connector latches 386 include angled planar surfaces 388 thatcorrespond to and engage with the latching portion 381. The internalfacets 387 of the fluid connector 360 engage the facets of the baselatch 376 and the base portion 380, thereby locking the fluid connector386 against rotational movement when the fluid connector 360 is engagedwith the base 374. The activation levers 362 and fluid connector latches386 pivot on a living hinge. By contacting the rigid stop 364 with theactivation levers 362, rigid stop 364 ensures that both of the fluidconnector latches 386 travel far enough to completely disengage from thebase 374, and provides a stable anchor for the activation levers 362during the handling of the fluid connector 360. Additionally, the rigidstop 364 helps prevent the fluid connector 360 from rocking whenattached to the base 374.

As shown in FIG. 71, the internal cavity 378 of the base 374 receives ametal wedge 388, a septum 161, and catheter 392. The wedge 388 has afunnel shape with a hollow center portion that narrows from a broad endto a narrow end. In contrast to other wedges recited herein, wedge 388has a shorter profile funnel portion, thus enabling a more compressedassembly with the septum cavity 378. The narrow end of the wedge 388 hasa tapered edge used to receive a terminal end of the catheter 392. Theseptum 161 is pre-slit and is retained within the internal cavity 378 ofthe base 374, and receives the bent cannula 372. The septum 161 may beheld in place within the base 374 by a press fit, or other exemplarymeans known in the art or disclosed herein, such as an adhesive. Theseptum 161 includes symmetric concave surfaces on both the top andbottom surfaces which aide in centering the cannula 372 through the slitin the septum 161 during assembly and improves the sealing ability ofthe septum 161 with respect to the cannula 372. A central horizontalportion or web of the septum 161 includes a convex top and bottomsurface that contain the slit. These convex surfaces provide additionalsealing pressure, keeping the slit sealed, particularly when externalforces are applied to the septum 161 when the fluid connector 386 isdisconnected from the base 374.

FIG. 73 illustrates a sectional view of the base 374.

FIG. 74 is a cross-sectional view of the wedge 388 illustrating the lowprofile and margarita-glass-like form.

FIGS. 75 and 76 illustrate an embodiment of a fluid connector 394 inwhich a lower rim 395 of the fluid path portion extends radiallyrelative to the outer side wall rather than being substantially coplanarwith the outer side wall. This configuration provides greater stabilitywhen the fluid connector 394 is connected to a base.

FIG. 77 is a perspective view of a base 396 in accordance with anembodiment of the present invention. In an interior, the base 396includes a plurality of support ribs 397. According to one embodiment,the support ribs 397 are sloped. According to another embodiment, thesupport ribs 397 are concave. The support ribs provide additionalsupport for a wedge to be inserted in the base 396. According to oneembodiment, the shape of each of the support ribs is complimentary tothe shape of the wedge to support the wedge along substantially all ofthe support rib. Alternatively, the support ribs can be shaped so thatthey contact the wedge at discrete points.

FIGS. 78-81 are cross-sectional views of alternative bases. Inparticular, these embodiments vary in their internal structure forreceiving and supporting the wedge. In FIG. 78, the interior of the base398 is beveled 399 and stepped 400 to transition to a convex taperedportion 401. These features can create a “well” to catch and collectdebris created during wedge installation. Such a well can be useful toinsure proper seating of the wedge and flexible cannula. Similarly, thebase 402 of FIG. 79 also has a well, but the transition portion 404 fromthe cylindrical portion 403 to the convex tapered portion 405 is concaveand is not stepped.

The base 406 of FIG. 80 is similar to the base 402 of FIG. 79, exceptthe transition 407 is convex. The base 408 has a flat step 409 thattransitions to a convex tapered portion 410. In an alternativeembodiment, the portion 410 is substantially conical.

It is also noted that in comparison with the embodiment of FIG. 65, inthe embodiments of FIGS. 78-81, the annular space surrounding thecentral, distal, columnar protrusion (or central column) extendsproximally further into the base. Additionally, the distal columnarprotrusion extends beyond the primary distal surface of the base. Asdiscussed in greater detail below, these differences can accommodatedifferent needle guards for protecting an introducer needle.

FIG. 82 illustrates a cross-sectional view of another exemplaryembodiment of a base 420. Features of the base 420 can beinterchangeable with each of the other exemplary bases previouslydiscussed. Base 420 includes an interior cavity 422 which can retain aseptum (not shown) and facilitate a fluid flow path between a fluidconnector (not shown) and a catheter (not shown), as previouslydiscussed in more detail. Base 420 includes a retention ring 424 locatedon a top portion of the base 420. The retention ring 424 can be fastenedto the base 420 via swaging heat, ultrasonic welding, an adhesive, or byany other fastening means known in the art. The retention ring 424prevents the septum from slipping out of the interior cavity 422 of thebase 420 (for example, when the fluid connector is removed) bydecreasing the diameter of the opening of the base 420. The retentionring can extend completely around the perimeter of the base opening.Alternatively the retention ring 424 can be a partial or discontinuousring. Alternatively, the retention ring can be fastened to the topsurface of the base 420, so that the retention ring at least partiallyoverlaps the opening of the base 420, effectively retaining the septumwithin the interior cavity 422 of the base 420. As another alternative,the septum can be retained within the interior cavity by swaging thematerial of the base 420 to form an integrated retaining ring.

FIG. 83 is a perspective bottom view of a fluid path portion 430 of afluid connector in accordance with an embodiment of the presentinvention. In comparison t the fluid path portion 339 of FIG. 60, thefluid path portion 430 has a stepped rear interior wall 432 and steppedinterior side walls 434. This configuration can increase the stabilityof the connection with the base by providing additional facets 436 and438 for contacting facets of the base latch and base portion of thebase.

FIG. 84 is a cross-sectional view of a base 440 in accordance with anembodiment of the present invention. Like the bases of FIGS. 78-81, onits distal side, the base 240 has a central column 442 from which thesoft catheter 444 protrudes, and the central column 442 extends distallybelow the primary distal surface 446 of the base 440. Additionally, theannular space 448 surrounding the central column 442 extends proximallyfurther into the base than the base of FIG. 65. The base 440, however,also has a lip 450 at the distal end of the central column 442 and anannular recess 452 on its distal face surrounding the soft catheter 444.The lip 450 and annular space 448 can accommodate a needle guard toprotect an introducer needle, as subsequently discussed in greaterdetail. The annular space 452 can provide flexibility for the softcatheter 444 and reduce instances of tearing during installation of thesoft catheter 444 into the base 440.

FIG. 85 is a perspective view of an infusion set assembly 500 inaccordance with an embodiment of the present invention. The assemblyincludes an insertion hub 502 with a hollow introducer needle 504connected thereto, and an infusion set base 506 that is connected to theinsertion hub 502. The base 506 includes an adhesive pad 508 to securethe base 506 to the skin of a patient, and a hollow base cannula 510.According to one embodiment, the base cannula is a soft plastic catheter510. In this embodiment, the introducer needle 504 passes through thesoft catheter 510 and extends beyond the proximal end of the softcatheter 510. It will be understood by one skilled in the art, however,that the present invention is not limited to a soft catheter. Forexample, the base cannula 510 may be a rigid metal cannula, in whichcase a separate introducer needle is not required. The assembly 500 alsoincludes a needle guard 520, which is shown in dotted lines in FIG. 85for clarity.

As shown in FIGS. 86-91, according to one embodiment, the needle guard520 is an integral, one-piece plastic structure that includes an upperor proximal portion 522 for connecting to the base 506 and a lower ordistal portion 524 for user or patient interaction. In other words,according to one embodiment, the needle guard 520 is integrally formedas a unitary structure.

Although other users can use the infusion set insertion assembly 500(for example, a health care professional), for brevity the user will bereferred to as “the patient” hereinafter. As best shown in FIGS. 86-88,the distal portion 524 includes touch points 526 that are sculpted in amanner to guide the patient in squeezing the lower portion 524. Forexample, the touch points 526 are wide and curved in a concave shape forcomfortable interaction with the patient's fingers. Additionally,according to one embodiment, the distal portion 524 of the needle guard520 includes a plurality of support ribs 528 on the interior thereof toincrease the structural rigidity of the distal portion.

As will be described in greater detail below, the proximal portion 522has a pair of opposing, inward cantilevered gripping portions 530 forselective connection with the base 506. In addition, both the proximaland distal portions 522 and 524 have axial cutouts (532 and 534,respectively) therein that effectively divide the needle guard 520 intoright and left sides. According to one embodiment, the proximal axialcutouts 532 and the distal axial cutouts 534 are axially aligned,thereby forming pairs of aligned cutouts. Disposed between the cutoutsand joining the right and left sides of the needle guard 520 is a pairof fulcrum webs 536.

The fulcrum webs 536 also provide a fulcrum for relative rotation of theright and left sides of the needle guard 520, as permitted by theflexibility of the plastic material of which it is made. As shown, forexample, in FIG. 89, as the patient presses the touch points 526 of thedistal portion 524 radially inward, the proximal portion 522correspondingly displaces radially outward (arrows A in FIG. 89) aboutthe fulcrum webs 536. Conversely, as the biasing force is removed (i.e.,the patient releases the radially inward pressing force), the distalportion 524 displaces radially outward about the fulcrum webs 536 andreturns to its initial, unbiased position, and the proximal portion 522correspondingly displaces radially inward about the fulcrum webs 536 toits initial, unbiased position (arrows B shown in dotted line).

As noted, the needle guard 520 is preferably made of a rigid butflexible plastic, such as, polypropylene. According to one embodiment,the needle guard 520 has a height of about 0.65″ (16.5 mm), a width ofabout 0.18″ (4.5 mm) at the proximal portion, and widths of about 0.34″(8.6 mm) and 0.45″ (11.4 mm) at the distal end of the needle guard 520.

FIG. 92 is a cross-sectional view of the needle guard 520 connected tothe base 506 and FIG. 93 is an enlarged view of a portion of FIG. 92.The insertion hub 502 and the introducer needle 504 are omitted fromFIGS. 93 and 94 for clarity. On its distal side, the base 506 has acentral column 540 from which the soft catheter 510 protrudes distally.One skilled in the art will appreciate, however, that embodiments of thepresent invention are not limited to the column being centrally locatedwith respect to the base. According to one embodiment, the soft catheteris held in the central column 540 by a metal wedge 542, the proximalside of which is covered by a septum 544 that seals the proximal end ofa port 546. The central column 540 has a middle portion that isundercut, thereby forming a lip 548. According to one embodiment, thebase 506 has an annular space surrounding the central column 540. Duringuse, the gripping portions 530 of the needle guard 520 engage the lip548 of the central column 540 to retain the needle guard 520 on the base506. According to on embodiment, as shown in FIG. 93, when connectedwith the base 506, a proximal portion of the needle guard 520 contactsthe proximal celling of the annular space surrounding the central column540.

Preferably, the external diameter of the lip 548 is slightly larger thanthe internal diameter of the gripping portions 530, and thus, wheninstalled on the base 506, the gripping portions are displaced ordeflected radially outward about the fulcrum webs 536 and thereby (dueto the resilience of the plastic material of which the needle guard 520is made) provide a radially-inward-directed gripping force to retain theneedle guard 520 on the base 506. Additionally, as best shown in FIG.93, the distal portions of the gripping portions 530 engage the proximalportion of the lip 548 to prevent undesired axial displacement of theneedle guard 520 relative to the base. But because the surface area ofengagement is so small, the amount of outward rotation of the grippingportions about the fulcrum webs 536 necessary to disengage the needleguard from the base 506 is also small.

The needle guard 520 is attached to the base 506 prior to shipping, toprotect the introducer needle 504 and the base cannula 510. Therefore,prior to inserting the infusion device into the skin, the patient mustfirst remove the needle guard 520. As described previously, the userpresses the touch points 526 together, thereby rotating the grippingportions 530 radially outward about the fulcrum webs 536 and disengagingthe gripping portions 530 from the central column 540 of the base 506.Subsequent to the disengagement, the patient completely removes theneedle guard 520, thereby exposing the introducer needle 504 andreadying the infusion device for insertion.

Thus, little or no axial force is required to separate the needle guard520 from the base 506. Further, by selecting materials and thedimensions of the fulcrum webs 536, the needle guard 520 requires only asmall amount of lateral force by the patient to disengage the grippingportions 530 from the central column 540. Further, embodiments of thepresent invention allow the needle guard 520 to be removed withoutdulling or causing damage to the introducer needle 504. Additionally,because little or no axial force is required to disengage the needleguard 520 from the base, the needle guard can be removed withoutinadvertently activating an introducer needle shielding mechanism.Further still, embodiments of the present invention permit highermanufacturing variation tolerances to reduce creep/aging affects andhigh stress levels in the part while retaining sufficient holding forceto prevent the needle guard 520 from being accidentally removed.Embodiments of the present invention provide a controlled deflection ofthe gripping portions 530 to produce a consistent retaining force with alarge tolerance and low removal force requirement. Moreover, incomparison with other commercially available needle guards, one benefitof embodiments of the present invention is that the patient has morecontrol when removing the needle guard. For example embodiments of thepresent invention reduce the risk of a potential needle stick or damageto the needle and/or cannula by eliminating the sometimes “jerky” motionof simply overcoming friction and pulling the needle guard free.

FIG. 94 illustrates how the patient can reattach the needle guard 520 tothe base 506 after withdrawal of the base 506 from the skin, even if thebase 506 remains connected with a fluid connector 550 (fluid connectortubing is omitted for clarity).

FIGS. 95-97 illustrate an infusion base 600 in accordance with anotherembodiment of the present invention. As shown in FIGS. 95-97, theinfusion base 600 has a base portion 602 and a disc portion 604. Thehorizontal distal portion of the base portion 602 has a an outer portion608 that has a reduced thickness in comparison to the reset of thehorizontal distal portion. In additional the outer portion 608 has aplurality of through holes 606, as subsequently discussed in greaterdetail.

According to one embodiment, the disc portion 604 is a flexible discportion 604, and the holes 606 and reduced thickness of the outerportion 608 facilitate bonding between the base portion 602 and theflexible disc portion 604. More specifically, the base portion 602 ismolded in a first shot, and the flexible disc portion 604 is molded in asecond shot, during which the material of the flexible disc portion 604flows around the outer portion 608 and through the holes 606. The shapeof the outer portion 608 provides a double overlapping joint with thematerial of the flexible disc portion 604 and the holes 606 provideadditional bonding surface area, as well as an additional mechanicalinterlock. In contrast, the embodiment of FIG. 4 has only a singleoverlapping joint for bonding.

In addition, as shown best in FIG. 95, the base portion 602 has facets614 on the top of the base latch 616. These facets 614 allow the flatvertical sides 618 of the base latch 616 to be thicker than inpreviously-described embodiments, for example, the embodiment of FIG.56, in which the top surface of the base latch 328 is rounded. Thisincreased thickness provides increased surface area, and thus, the flatvertical sides 618 provide stronger engagement between the base 600 anda fluid connector, and stronger resistance to rotational torque betweenthe fluid connector and the base 600.

FIG. 98 is a cross-sectional view of a metal wedge 640 in accordancewith an embodiment of the present invention. The wedge 640 is used forsecuring a flexible catheter to a base. The wedge 640 has an initialflared portion 642 adjacent to a nose portion 644. A flat portion 644 isproximally adjacent to the initial flared portion 642, and a secondaryflared portion 646 is proximally adjacent to the flat portion 644. Incomparison to some of the previously-discussed wedges, the wedge 640 hasa steeper angle to the initial flared portion 642. Generally, duringassembly, contact of the introducer needle with the wedge (and thus,dulling of the introducer needle) may occur some percentage of the timedue to positional variation of the needle relative to the wedge whenpassing the introducer needle through the wedge into the final assembledposition. A steeper angle, however, such as that of the initial flaredportion 642, immediately outside the nose portion 644 can minimize theimpact to the introducer needle and help guide it through the wedge 640and maintain sharpness during assembly.

In each of the herein disclosed embodiments and in other alternativeembodiments, the components of the infusion set can be made ofinjection-molded polypropylene, polyethylene, acrylonitrile butadienestyrene polymers, polyesters such as polyethylene terephthalate orsimilar materials, and/or bio-based resins such as polylactide,starch-filled polypropylene, or polyhydroxyalkanoates. The catheter canbe a separate component or it can be injection-molded as part of thebase assembly, either as a single part or as a coinjection-molded partusing two resins. Soft shot components can be of ethylene vinyl acetate,thermoplastic urethanes, styrenic thermoplastic elastomers, cellulosicelastomers, copolyester elastomers, or similar materials.

Although only a few exemplary embodiments of the present invention havebeen described in detail above, those skilled in the art will readilyappreciate that many modifications are possible in the exemplaryembodiments without materially departing from the novel teachings andadvantages of this invention. Accordingly, all such modifications areintended to be included within the scope of this invention as defined inthe appended claims and their equivalents.

What is claimed is:
 1. A needle guard for guarding a sharp cannula of aninfusion device, the needle guard comprising: a proximal portion forconnecting to the base of the infusion device; and a distal portion foruser interaction; wherein the proximal and distal portions each includeat least one axial cutout that divides the needle guard into first andsecond lateral sides; and wherein a fulcrum web is disposed between theproximal and distal axial cutouts to join the first and second lateralsides of the needle guard and provide a fulcrum for relative rotation ofthe first and second lateral sides of the needle guard.
 2. The needleguard according to claim 1, wherein the needle guard is integrallyformed as a unitary structure.
 3. The needle guard according to claim 1,wherein: the proximal portion includes a pair of axial cutouts; thedistal portion includes a pair of axial cutouts; the proximal axialcutouts are substantially aligned with the distal axial cutouts, formingpairs of aligned cutouts; and the needle guard further comprises a pairof fulcrum webs respectively disposed between the pairs of alignedcutouts.
 4. The needle guard according to claim 1, wherein the distalportion includes a pair of concave sculpted portions for interactionwith the user's fingers.
 5. The needle guard according to claim 1,wherein the distal portion includes a plurality of support ribs toincrease the structural rigidity of the distal portion.
 6. The needleguard according to claim 1, wherein the proximal portion includes a pairof opposing, inward-cantilevered gripping portions for connecting withthe infusion device.
 7. A combination, comprising: the needle guardaccording to claim 6; and a base of the infusion set, wherein the baseincludes distally-extending column from which a cannula protrudesdistally; the column having an undercut middle portion, thereby forminga lip at its distal end; wherein the gripping portions of the needleguard engage the lip to selectively retain the needle guard on the base.8. The combination according to claim 7, wherein when connected with thebase, a proximal portion of the needle guard contacts the proximalcelling of an annular space surrounding the column.
 9. The combinationaccording to claim 8, wherein the column extends distally beyond asubstantially planar distal surface of the base.